Physical Sciences and Mathematics Commons^™

Synthesis Of Linear Oligo[N]Catenanes Via Orthogonal Metal Templation, Nathan Colley

Arts & Sciences Electronic Theses and Dissertations

No abstract provided.

Biomedical Applications Of Polarimetry, Nathaniel Owen King

McKelvey School of Engineering Theses & Dissertations

Non- or minimally-invasive data collection is highly desirable for gathering the broad base of information that facilitates moving technology to the point of care. Polarimetry has been making this transition for years. Early forms of polarization-sensitive optics involved custom multiplexing a series of images to generate a single image, but today’s snapshot polarimeters are readily commercially available.

The research presented in this dissertation advances three areas of polarimetric imaging: First, this research develops a reflectance-based measurement for tracking changes in the alignment of dynamically loaded soft tissue, specifically tendon. This work highlights a range of mounting angles across which signal …

Wavelet Coherence Analysis With An Application Of Brain Images, Yiqian Fang

Arts & Sciences Electronic Theses and Dissertations

Wavelet analysis has become an emerging method in a wide range of applications with non-stationary data. In this work, we apply wavelets to tackle the problem of estimating dynamic association in a collection of multivariate non-stationary time series. Coherence is a common metric for linear dependence across signals. However, it assumes static dependence and does not sufficiently model many biological processes with time-evolving dependence structures. We explore continuous wavelet analysis for modeling and estimating such dynamic dependence under the replicated multivariate time series settings. Wavelet transformation provides a decomposition of signals that localizes in both time and frequency domains, hence …

New Physics With Ultra-High Energy Neutrinos, Yicong Sui

Arts & Sciences Electronic Theses and Dissertations

Ultra-high energy (UHE) astrophysical neutrinos are unique in the sense that they are the

only known particles that could travel through incredibly long distance unattenuated, with

TeV to EeV energy, much higher than the most powerful man-made collider could provide.

The detection of these UHE neutrinos has ushered a new era in neutrino astrophysics, as they

carry important information directly from the inside of energetic astrophysical objects. On the

other hand, from the particle physics point of view, the UHE neutrinos also offer a new window

of opportunity for studying beyond the Standard Model (BSM) phenomena. This is the main …

Production Of Medical Radioisotopes Using Titanium Accelerator Targets, Christopher Shaun Loveless

Arts & Sciences Electronic Theses and Dissertations

Theranostic radiopharmaceuticals enable diagnostic imaging and radionuclide therapy in patients using a single molecular agent labeled with a diagnostic-therapeutic pair (e.g., 68Ga/177Lu) or a theranostic radionuclide (e.g., 131I). This theranostic approach can help inform patient-specific treatment plans and improve clinical outcomes. Radionuclide pairs used in theranostic agents fall into two categories: pseudo matched-pairs (e.g., 68Ga/177Lu) and matched-pairs (e.g., 124I/131I). Pseudo matched-pair radionuclides have similar chemistries and pharmacokinetics when bound to the same bioconjugate molecule. In contrast, identical chemistries and pharmacokinetics can be obtained by using the matched-pair radionuclides.

The isotopes of Sc include two diagnostic radioisotopes, 43Sc & 44Sc, and …

Experimental Constraints On Igneous Iron Isotopic Fractionation And Diffusion, Kelsey Brianne Prissel

Arts & Sciences Electronic Theses and Dissertations

The chapters of this dissertation detail experimental studies that have been conducted in order to determine the diffusivity of iron in the mineral ilmenite (FeTiO3) and the high-temperature behavior of iron isotopes during magma crystallization. The experimental study in Chapter 2 is the first to quantify the rates of cation diffusion in ilmenite. Integrating experimentally determined Fe-Mg and Fe-Mn interdiffusivities with disequilibrium preserved in ilmenite grains from natural volcanic samples, this work has established a new geospeedometry tool with which to estimate the time between magmatic perturbation and eruption on the timescale of hours to months. Chapter 3 investigates the …

Separating Signal From Noise In High-Density Diffuse Optical Tomography, Arefeh Sherafati

Arts & Sciences Electronic Theses and Dissertations

High-density diffuse optical tomography (HD-DOT) is a relatively new neuroimaging technique that detects the changes in hemoglobin concentrations following neuronal activity through the measurement of near-infrared light intensities. Thus, it has the potential to be a surrogate for functional MRI (fMRI) as a more naturalistic, portable, and cost-effective neuroimaging system. As in other neuroimaging modalities, head motion is the most common source of noise in HD-DOT data that results in spurious effects in the functional brain images. Unlike other neuroimaging modalities, data quality assessment methods are still underdeveloped for HD-DOT. Therefore, developing robust motion detection and motion removal methods in …

Landesque Capital And Community Organization In A Maya Economic Center: A Case Study At Salinas De Los Nueve Cerros, Guatemala, Alexander Ernesto Rivas

Arts & Sciences Electronic Theses and Dissertations

Many ancient Maya lowland cities developed water-rich landscapes that met the multiple needs of growing populations. The development of landesque capital, in which permanent changes in infrastructure, water procurement, and agricultural productivity are best understood at sites with a long history of occupation. Salinas de los Nueve Cerros was an ancient Maya center that was occupied for approximately 2000 years, surviving the ‘Maya Collapse.’ This site, located in the Maya lowlands, had ties to both highland and lowland communities through its primacy in exporting salt. However, what is not yet understood is whether the commercial population of Nueve Cerros practiced …

Specificity Of Ssb Binding To Its Interacting Proteins And Multiple Allosteric Effects Of Ssb C-Terminal Tail On Assembly And Dna Binding Of E. Coli Recor Proteins, Min Kyung Shinn

Arts & Sciences Electronic Theses and Dissertations

The homo-tetrameric E. coli single strand (ss) DNA binding (SSB) protein is an essential component in DNA maintenance for its role in binding and protecting single stranded DNA intermediates via its N-terminal DNA binding domain (DBD). SSB also acts as a hub to recruit at least 17 SSB interacting proteins (SIPs) involved in DNA replication, recombination, and repair via its 9 amino acid C-terminal acidic tip region. A 56 amino acid intrinsically disordered linker connects the DBD and the acidic tip and plays a role in cooperative binding to ssDNA. Using isothermal titration calorimetry, I determined that the SSB-Ct peptides …

Flux Variability In Gamma-Ray Blazars, Benjamin Groebe

Arts & Sciences Electronic Theses and Dissertations

Blazars, among the most luminous objects in the sky, are extreme members of the class of active galactic nuclei featuring powerful outflows of relativistic particles in the form of jets pointed towards the observer. They display strong flux variability in all observed wavebands and on all observed timescales, with significant changes in flux observed in some sources over periods of as short as minutes. These remarkable observations have led to open questions regarding the nature of particle acceleration in the jets, location of the radiating particles along the jet, and the connection between jet emission and rate of accretion onto …

Peer-Led Team Learning In Calculus-Based Introductory Physics: Implementation And Evaluation, Siera Maia Stoen

Arts & Sciences Electronic Theses and Dissertations

Robust evidence shows that Peer-led Team Learning (PLTL) improves the academic success of college students in introductory Science, Technology, Engineering, and Mathematics (STEM) courses. However, further research is needed to gain a fuller understanding of the benefits of PLTL and the aim of this dissertation is to explore two key and understudied questions surrounding the effects of PLTL. First, does deviating from the optimal implementation of PLTL change its effectiveness? Second, what specific outcomes, in addition to academic success (e.g., exam scores), does PLTL improve? This dissertation will provide a fuller picture of the impact of PLTL by examining its …

Structural Organization And Chemical Activity Revealed By New Developments In Single-Molecule Fluorescence And Orientation Imaging, Tianben Ding

McKelvey School of Engineering Theses & Dissertations

Single-molecule (SM) fluorescence and its localization are important and versatile tools for understanding and quantifying dynamical nanoscale behavior of nanoparticles and biological systems. By actively controlling the concentration of fluorescent molecules and precisely localizing individual single molecules, it is possible to overcome the classical diffraction limit and achieve 'super-resolution' with image resolution on the order of 10 nanometers.

Single molecules also can be considered as nanoscale sensors since their fluorescence changes in response to their local nanoenvironment. This dissertation discusses extending this SM approach to resolve heterogeneity and dynamics of nanoscale materials and biophysical structures by using positions and orientations …

Development And Application Of Mass Spectrometry-Based Approaches For Protein Higher Order Structure Analysis And Protein-Protein Interaction Characterization, Mengru Zhang

Arts & Sciences Electronic Theses and Dissertations

Proteins, one of the most fundamental biomolecules, adopt unique higher order structures (HOS) to enable diverse biological functions. Deciphering protein HOS is crucial to gain deeper insights of their working mechanisms and to develop biotherapeutics. Mass spectrometry (MS)-based approaches evolved rapidly in the past 30 years and are now playing critical roles in protein HOS characterization. One of those approaches is MS-based footprinting whose principle is to map the solvent accessible surface area (SASA) to deliver structural information. Protein footprinting can be achieved by reversible labeling, e.g., hydrogen-deuterium exchange (HDX), and by irreversible labeling using radical-based reagents or other targeted …

Growth Of Small Particles In Nonequilibrium Plasmas, Necip Berker Üner

McKelvey School of Engineering Theses & Dissertations

Nonequilibrium plasma (NEP) is an extraordinary environment for material synthesis. NEP is comprised of hot electrons with temperatures greater than 10000 K and of cold ions and neutrals that are usually at few hundred kelvins above room temperature. Due to this large difference in species’ temperatures, the assumption of local thermal equilibrium does not hold in NEP. Therefore, NEP can act as a unique processor of mass, and it can transform materials along pathways that are not accessible by methods wherein local thermal equilibrium is valid. For decades, NEPs have been employed in the semiconductor industry to manufacture many thin …

X-Rays From Warped Black Hole Accretion Disks, Quincy Abarr

Arts & Sciences Electronic Theses and Dissertations

In this thesis, I present the results from my research to better understand accretion onto black holes and neutron stars based on spectropolarimetric X-ray observations.

I have developed a general relativistic ray-tracing code which simulates X-rays from warped accretion disks around black holes.

I used this to predict the polarization of the thermal X-ray emission and the energy spectrum the reflected power law emission.

Both of these can be used to measure properties of black hole systems, such as the spin parameter and the inclination of the observer to its spin axis.

My results enable the measurement of these parameters …

Domain Specific Computing In Tightly-Coupled Heterogeneous Systems, Anthony Michael Cabrera

McKelvey School of Engineering Theses & Dissertations

Over the past several decades, researchers and programmers across many disciplines have relied on Moores law and Dennard scaling for increases in compute capability in modern processors. However, recent data suggest that the number of transistors per square inch on integrated circuits is losing pace with Moores laws projection due to the breakdown of Dennard scaling at smaller semiconductor process nodes. This has signaled the beginning of a new “golden age in computer architecture” in which the paradigm will be shifted from improving traditional processor performance for general tasks to architecting hardware that executes a class of applications in a …

Convex Relaxations For Particle-Gradient Flow With Applications In Super-Resolution Single-Molecule Localization Microscopy, Hesam Mazidisharfabadi

McKelvey School of Engineering Theses & Dissertations

Single-molecule localization microscopy (SMLM) techniques have become advanced bioanalytical tools by quantifying the positions and orientations of molecules in space and time at the nanoscale. With the noisy and heterogeneous nature of SMLM datasets in mind, we discuss leveraging particle-gradient flow 1) for quantifying the accuracy of localization algorithms with and without ground truth and 2) as a basis for novel, model-driven localization algorithms with empirically robust performance. Using experimental data, we demonstrate that overlapping images of molecules, a typical consequence of densely packed biological structures, cause biases in position estimates and reconstruction artifacts. To minimize such biases, we develop …

Investigating Single Precision Floating General Matrix Multiply In Heterogeneous Hardware, Steven Harris

McKelvey School of Engineering Theses & Dissertations

The fundamental operation of matrix multiplication is ubiquitous across a myriad of disciplines. Yet, the identification of new optimizations for matrix multiplication remains relevant for emerging hardware architectures and heterogeneous systems. Frameworks such as OpenCL enable computation orchestration on existing systems, and its availability using the Intel High Level Synthesis compiler allows users to architect new designs for reconfigurable hardware using C/C++. Using the HARPv2 as a vehicle for exploration, we investigate the utility of several of the most notable matrix multiplication optimizations to better understand the performance portability of OpenCL and the implications for such optimizations on this and …

Real-Time Communication In Cloud Environments, Chong Li

McKelvey School of Engineering Theses & Dissertations

Real-time communication is critical to emerging cloud applications from smart cities to industrial automation. The new class of latency-critical applications requires latency differentiation and performance isolation in a highly scalable fashion in a virtualized cloud environments. This dissertation aims to develop novel cloud architecture and services to support real-time communication at both the platform and infrastructure layers. At the platform layer, we build SRTM, a scalable and real-time messaging middleware (platform) that features (1) latency differentiation, (2) service isolation through rate limiting, and (3) scalability through load distribution among messaging brokers. A key contribution of SRTM lies in the exploitation …

Csp-Completeness And Its Applications, Alexander Durgin

McKelvey School of Engineering Theses & Dissertations

We build off of previous ideas used to study both reductions between CSPrefutation problems and improper learning and between CSP-refutation problems themselves to expand some hardness results that depend on the assumption that refuting random CSP instances are hard for certain choices of predicates (like k-SAT). First, we are able argue the hardness of the fundamental problem of learning conjunctions in a one-sided PAC-esque learning model that has appeared in several forms over the years. In this model we focus on producing a hypothesis that foremost guarantees a small false-positive rate while minimizing the false-negative rate for such hypotheses. Further, …

Toward Efficient Scheduling For Parallel Real-Time Tasks On Multiprocessors, Son Ngoc Dinh

McKelvey School of Engineering Theses & Dissertations

Modern real-time applications are becoming more demanding computationally while their temporal requirements, dictated by the physical world, often remain unchanged. This coupled with the increasing prevalence of multiprocessors in real-time systems necessitates that highly computation-demanding real-time tasks need to be parallelized to exploit the parallelism offered by the underlying hardware, in order to satisfy their temporal constraints. Scheduling parallel real-time tasks, however, introduces a new layer of complexity due to the allowance for intra-task parallelism. This dissertation addresses the problem of scheduling parallel real-time tasks in which tasks may (or may not) access shared non-processor resources, such as in-memory buffers …

Transport In Neutron Star Mergers, Steven Patrick Harris

Arts & Sciences Electronic Theses and Dissertations

Neutron star mergers are the only situation in nature in which we find matter compressed to several times nuclear saturation density and temperatures of several tens of MeV. By observing and numerically simulating neutron star mergers, we can learn about the nature of matter at high temperatures and densities. Neutron star merger simulations evolve Einstein's equations of general relativity coupled to the equations of relativistic hydrodynamics along with a nuclear equation of state, which describes the neutron star matter. Many simulations also take into account neutrino transport and electrodynamics. The purpose of this thesis is to see whether other physical …

Operator Noncommutative Function Theory And Partial Matrix And Operator Convexity, Mark E. Mancuso

Arts & Sciences Electronic Theses and Dissertations

No abstract provided.

Measurement, Dissipation, And Quantum Control With Superconducting Circuits, Patrick Harrington

Arts & Sciences Electronic Theses and Dissertations

The interaction between a superconducting circuit and its environment can cause decoherence. However, interactions with an environment are necessary for quantum state preparation and measurement. Through the dynamics of open quantum systems, the environment is a resource to control and readout superconducting circuit states. I present an experimental result demonstrating qubit state stabilization from engineered dissipation with a microwave photonic crystal. In addition, I discuss the statistical arrow of time in the dynamics of continuous quantum measurement. These results demonstrate an interplay between open quantum system dynamics and statistics, which highlights the role of both dissipation and measurement for quantum …

Molecular Insights Into Microbial Adhesion, Roger Davies Klein

Arts & Sciences Electronic Theses and Dissertations

Antibiotic-resistant bacterial infections are a serious and immediate threat to global public health. In the United States alone, over 2 million individuals develop antibiotic-resistant infections annually, resulting in 23,000 deaths and $20 billion in excess health care costs. Virulence factors that allow bacteria to invade and persist within the host are promising targets for novel antimicrobial agents that could be used to curb the spread of antibiotic resistance. Development of therapeutics that can selectively eliminate pathogenic bacteria while sparing the beneficial host microbiota requires a detailed molecular understanding of critical virulence factors that facilitate interactions between pathogens and their environments. …

Internal Structures And Spin Evolutions Of Small Bodies In The Solar System And Their Geophysical Implications: A Case Study On Ceres, Vesta, And Arrokoth, Xiaochen Mao

Arts & Sciences Electronic Theses and Dissertations

Asteroids and Kuiper belt objects are for the most part the remnant planetesimals that have not been able to form into planets. These small bodies’ evolutionary pathways encode information from the early days of the Solar System. Recent space missions such as Dawn and New Horizons have now made detailed geological investigations of small bodies (i. e. , Ceres, Vesta, and Arrokoth) possible. In this thesis, I use geophysical modeling to study small body internal structure and to investigate spin history under the influence of impacts. I analyze the gravity and shape data obtained by Dawn of Ceres and make …

A Different Approach To Endpoint Weak-Type Estimates For Calder̟N-Zygmund Operators, Cody B. Stockdale

Arts & Sciences Electronic Theses and Dissertations

The aim of this thesis is to investigate weak-type inequalities for linear and multilinear Calderón-Zygmund operators in Euclidean and weighted settings using the Calderón- Zygmund decomposition and ideas inspired by Nazarov, Treil, and Volberg. In the linear setting, a new simple proof of the classical weak-type (1; 1) property is given with motivation For multilinear Calderón-Zygmund operators, the Nazarov-Treil-Volberg ideas lead to a new proof of the weak-type (1,. . . ,1; 1/m) estimate. Connecting the weighted and multilinear settings, a weighted weak-type estimate for multilinear Calderón-Zygmund operators is proved. Two proofs for the weighted multilinear inequality are presented – …

Studies Of Maximum Supercooling And Stirring In Levitated Liquid Metallic Alloys, Mark Edward Sellers

Arts & Sciences Electronic Theses and Dissertations

Nucleation—or the formation of some cluster in a medium undergoing a phase transition—is usually the initial step in a phase transition. However, this process is still not fully understood, as outstanding questions related to the role of structure, local order, and diffusion remain unanswered. Systematic supercooling studies on metallic liquids performed using electrostatic and electromagnetic (ESL and EML, respectively) will be presented and discussed within the context of several nucleation theories, such as the Classical Nucleation Theory, Diffuse Interface Theory, and Coupled-Flux theory. To study the role of diffusion on nucleation, studies on the International Space Station using the on-board …

Supertiger Elemental Abundances For The Charge Range $41 \Leq Z \Leq 56$, Nathan Elliot Walsh

Arts & Sciences Electronic Theses and Dissertations

No abstract provided.

Thermophysical Properties And Phase Transformations In Metallic Liquids And Silicate Glasses, Daniel Christian Van Hoesen

Arts & Sciences Electronic Theses and Dissertations

The first quantitative measurements of the electrical resistivity in binary metallic liquids, used to probe local order in the liquid, are reported in this dissertation. The electrical resistivity is very sensitive to short and medium range ordering because the electron mean free path is approximately the same length scale as the atomic spacing. Particular attention is given to the resistivity value at a crossover temperature that, based on molecular dynamics (MD) simulations, is the onset of cooperative motion in liquid alloys. Experimental evidence for the crossover is found in measurements of the shear viscosity, a dynamical property. An indication of …